Search Results

Subjective Visual Vertical and Eye-Head Coordination (Roll) with Brain Stem Lesions

Dieterich Marianne and Thomas Brandt

in The Head-Neck Sensory Motor System

The ocular tilt reaction (OTR) models a fundamental pattern of coordinated eye-head roll motion based on utricular/saccular as well as vertical canal input, made by the gaviceptive pathways from the ... More

The ocular tilt reaction (OTR) models a fundamental pattern of coordinated eye-head roll motion based on utricular/saccular as well as vertical canal input, made by the gaviceptive pathways from the labyrinths via pontomedullary vestibular nuclei to the rostral midbrain tegmentum. The direction of eye-head tilt in roll with brain stem lesions and the skew deviation and cyclorotation is discussed in this chapter. It is concluded that all patients with the OTR showed significant deviations of the subjective visual vertical (SVV) in the direction of the head tilt. The single features of the OTR, perceptual and oculomotor, can be induced separately depending on the site of the lesion.Less

Head Position versus Head Motion in the Inhibition of Horizontal Postrotary Nystagmus

Eberhard Koenig, Wilhelm Dengler, Michael Fetter, Asta Hann, and Johannes Dichgans

in The Head-Neck Sensory Motor System

A tilt from the prior erect position to a horizontal head position stimulates not only the otoliths but also the vertical semicircular canals and neck afferents. To clarify further the inputs needed ... More

A tilt from the prior erect position to a horizontal head position stimulates not only the otoliths but also the vertical semicircular canals and neck afferents. To clarify further the inputs needed for inhibition, the authors compared static head tilts having only one dynamic component with head movements giving predominantly dynamic components. In addition, intermittent head tilts of different durations and at different times after the stop were used to study the dynamics of the “dumping” process. Head tilts after the presumed end of the peripheral input were used to study whether the effect of the inhibitory stimulus changes in the absence of peripheral input from the horizontal semicircular canals.Less

IMAGE PROCESSING AND SUPER-RESOLUTION SCHEMES

JOHN C. H. SPENCE

in High-Resolution Electron Microscopy

This chapter describes methods intended to extend resolution beyond the Scherzer limit. Methods for combining images in a through-focus series are reviewed, and coherent detection with Wiener ... More

This chapter describes methods intended to extend resolution beyond the Scherzer limit. Methods for combining images in a through-focus series are reviewed, and coherent detection with Wiener filtering explained. Optimization methods and incorporation of a-priori information are reviewed, and the connection with Baysian statistics is made. Several super-resolution methods are then outlined — tilt series, off-axis electron holography, combining imaging with diffraction data, ptychography, ronchigrams, shadow imaging, in-line holography, and diffractive imaging. Aberration correction is described (and expressions given for the optimum choice of focus and spherical aberration constant), and a section is given which summarizes approaches to the multiple-scattering inversion problem.Less

Curtain of Light, Tilted Mirror

Keith Garebian

in The Making of Cabaret

Because of an epiphany he experienced in Moscow's Taganka Theater, Harold Prince was able to find his central metaphor that was appropriate not only to German society in the Third Reich but to ... More

Because of an epiphany he experienced in Moscow's Taganka Theater, Harold Prince was able to find his central metaphor that was appropriate not only to German society in the Third Reich but to America in the sixties as well. This chapter explains how Prince was able to achieve the physical look of his musical through the lighting design of Jean Rosenthal and the set design of Boris Aronson. Rosenthal's clever lighting demarcated two worlds: the real world (the cabaret scenes and the book scenes), and the limbo area (the mind). The Emcee's material was divided between scenes in the cabaret and metaphorical numbers representing changes in the German mind. Aronson extended Prince's central metaphor by a mirror tilted over the stage to reflect both the performers and the audience. This was the greatest visual coup because it forced audiences to interrogate their own relationship to the play's political and moral significance.Less

Broadway Presentational

Keith Garebian

in The Making of Cabaret

Cabaret was a great occasion for Broadway, signaling that a musical could be derivative (of Brecht–Weill) but also daring (combining politics, history, and promiscuity). This ... More

Cabaret was a great occasion for Broadway, signaling that a musical could be derivative (of Brecht–Weill) but also daring (combining politics, history, and promiscuity). This chapter reveals that opening night was both brilliant and schizophrenic. The first thing the audience noticed while entering the theater was itself in Aronson's huge tilted mirror. The jangled cabaret music provided the fundamental beat of the entertainment, and with the Emcee's garish role and the Kit Kat band and dancers, the cabaret world became the dominant, immediate world. With a detailed description of what transpired onstage, the chapter captures the show's excitement, triumphs, and shortcomings and offers the main newspaper critics' evaluations of the musical while also pinpointing points of public controversy and agreeing with Walter Kerr that the show opened the door to picaresque themes for musicals.Less

Personality Science and the Northern Tilt: As Positive as Possible Under the Circumstances

Brian R. Little

in Designing Positive Psychology: Taking Stock and Moving Forward

This chapter reflects on how positive psychology and personality science have co-evolved and how they may continue to do so. The key substantive question it explores is this: to what extent and in ... More

This chapter reflects on how positive psychology and personality science have co-evolved and how they may continue to do so. The key substantive question it explores is this: to what extent and in what ways are positive emotions, orientations, and actions critical for human well-being? Drawing on research in personality science, it makes the case that for some individuals, under certain circumstances, adopting a so-called northern tilt will be highly adaptive. Under other circumstances, however, an upward-bound approach to life might be less adaptive. At its worst, unmitigated positivity might catch us unawares and bring us to our knees. The chapter begins by taking stock of some shared themes in positive psychology and the study of personality. It starts with the most important common concern—the conceptual and empirical analysis of human well-being and the diverse forms it may take. It then discusses three major sources of influence on human well-being: stable features of persons such as traits and basic orientations, volitional action such as personal projects, and influences within the social ecology where traits are expressed and projects are pursued. After taking stock, it proposes three areas for future exploration that blend the aspirations of both of these vital fields of inquiry.Less

Influence of Neck Receptor Stimulation on Eye Rotation and on the Subjective Vertical: Experiments on the Tilt Table, under Water, and in Weightlessness

Joachim Wetzig and Rudolf J. Von Baumgarten

in The Head-Neck Sensory Motor System

Since the head is pivoted in all directions on the trunk, verticality of the trunk and equilibrium must be computed from at least two sources, the otolith system and the proprioceptive system of the ... More

Since the head is pivoted in all directions on the trunk, verticality of the trunk and equilibrium must be computed from at least two sources, the otolith system and the proprioceptive system of the neck. To study the influence of neck receptors on subjective space orientation and on eye movement is quite a tough task because most procedures on the ground include neck receptor stimulation and the vestibular organ at the same time. Experiments were conducted on a land-based special tilt table that allows tilting the whole body together with the head or tilting the head relative to the body or maintaining a fixed position of the head while deflecting the body against the head.Less

Gravitational, Inertial, and Coriolis Force Influences on Nystagmus, Motion Sickness, and Perceived Head Trajectory

James R. Lackner and Paul DiZio

in The Head-Neck Sensory Motor System

An intricate pattern of stimulation is generated when a rotating individual tilts his head about an axis that is not parallel to the axis of rotation. His semicircular canals undergo cross-coupled ... More

An intricate pattern of stimulation is generated when a rotating individual tilts his head about an axis that is not parallel to the axis of rotation. His semicircular canals undergo cross-coupled angular accelerations, and his head and otolith organs are exposed to a Coriolis force. Such head movements elicit nystagmus, motion sickness symptoms, and disorientation. The disorientation has two major components: during the head movement, the individual will misperceive the actual trajectory of his head in relation to his torso, and for some time afterward, he will have a confusing illusion that his whole body is rotating. If an individual seated at the center of the platform rotating counterclockwise at constant angular velocity tilts his head backward, then his yaw canal receives a clockwise velocity impulse because it loses angular momentum on moving out of the plane of rotation.Less

Adaptation to Complex Visual Patterns in Humans and Monkeys

David A. Leopold and Igor Bondar

in Fitting the Mind to the World: Adaptation and After-Effects in High-Level Vision

This chapter explores aftereffects from a particular point of view, namely, with regard to the complexity of the stimuli that generate them. It first asks, given the hierarchical structure of the ... More

This chapter explores aftereffects from a particular point of view, namely, with regard to the complexity of the stimuli that generate them. It first asks, given the hierarchical structure of the visual system, and the many types of stimuli for which adaptation is effective, does stimulus complexity affect the expression of the well-studied tilt aftereffect (TAB)? If aftereffects are a product of selective sensory neurons, complex stimuli might be expected to elicit very different effects, reflecting their processing at higher processing stages in the visual hierarchy. The chapter then focuses on aftereffects generated by adaptation to faces, which have recently shed new light on the brain mechanisms of both aftereffects and face processing.Less

“Recover the Paths”: Salvage in Tom Franklin’s Fiction

Joan Wylie Hall

in Rough South, Rural South: Region and Class in Recent Southern Literature

This chapter discusses Tom Franklin's fiction. Franklin was born in Dickinson, Alabama, in 1963. Growing up, he watched horror films, created stories for toy action figures, and wrote and illustrated ... More

This chapter discusses Tom Franklin's fiction. Franklin was born in Dickinson, Alabama, in 1963. Growing up, he watched horror films, created stories for toy action figures, and wrote and illustrated his own comic books. His family, devout Pentecostals, demonstrated its faith through healings and speaking in tongues. When Franklin was eighteen, his family moved to Mobile, where he attended the University of South Alabama, earning a BA in English. In 1998 he earned an MFA at the University of Arkansas, where he met and married poet Beth Ann Fennelly. His first book, Poachers, appeared the next year, and he has since published three novels: Hell at the Breech (2003), Smonk (2006), and Crooked Letter, Crooked Letter (2010). In late 2013 Franklin published The Tilted World, a novel co-written with Fennelly. Poachers is set in a contemporary South whose landscapes have long been under assault. “Grit,” the first story, displays many conventions of Rough South literature.Less

Perfectoid rings

Peter Scholze and Jared Weinstein

in Berkeley Lectures on p-adic Geometry: (AMS-207)

This chapter examines perfectoid spaces. A Huber ring R is Tate if it contains a topologically nilpotent unit; such elements are called pseudo-uniformizers. One can more generally define when an ... More

This chapter examines perfectoid spaces. A Huber ring R is Tate if it contains a topologically nilpotent unit; such elements are called pseudo-uniformizers. One can more generally define when an analytic Huber ring is perfectoid. There are also notions of integral perfectoid rings which are not analytic. In this course, the perfectoid rings are all Tate. It would have been possible to proceed with the more general definition of perfectoid ring as a kind of analytic Huber ring. However, being analytic is critical for the purposes of the course. The chapter then looks at tilting and sousperfectoid rings. The class of sousperfectoid rings has good stability properties.Less

Perfectoid spaces

Peter Scholze and Jared Weinstein

in Berkeley Lectures on p-adic Geometry: (AMS-207)

This chapter offers a second lecture on perfectoid spaces. A perfectoid Tate ring R is a complete, uniform Tate ring containing a pseudo-uniformizer. A perfectoid space is an adic space covered by ... More

This chapter offers a second lecture on perfectoid spaces. A perfectoid Tate ring R is a complete, uniform Tate ring containing a pseudo-uniformizer. A perfectoid space is an adic space covered by affinoid adic spaces with R perfectoid. The term “affinoid perfectoid space” is ambiguous. The chapter then looks at the tilting process and the tilting equivalence. The tilting equivalence extends to the étale site of a perfectoid space. Why is it important to study perfectoid spaces? The chapter puts forward a certain philosophy which indicates that perfectoid spaces may arise even when one is only interested in classical objects.Less

Diamonds

Peter Scholze and Jared Weinstein

in Berkeley Lectures on p-adic Geometry: (AMS-207)

This chapter investigates the notion of a diamond. The idea is that there should be a functor which “forgets the structure morphism to Zp.” The desired quotient in the example provided in the chapter ... More

This chapter investigates the notion of a diamond. The idea is that there should be a functor which “forgets the structure morphism to Zp.” The desired quotient in the example provided in the chapter exists in a category of sheaves on the site of perfectoid spaces with pro-étale covers. The chapter then defines pro-étale morphisms between perfectoid spaces. A morphism of perfectoid spaces is pro-étale if it is locally (on the source and target) affinoid pro-étale. The intuitive definition of diamonds involved the tilting functor in case of perfectoid spaces of characteristic 0. For this reason, diamonds are defined as certain pro-étale sheaves on the category of perfectoid spaces of characteristic p.Less

Epilogue

David M. Bergeron

in Shakespeare's London 1613

This conclusion peers into the early days of 1614, including the birth of the first royal grandchild, Elizabeth’s first son, in early January, confirming the ‘German connection’ for the British royal ... More

This conclusion peers into the early days of 1614, including the birth of the first royal grandchild, Elizabeth’s first son, in early January, confirming the ‘German connection’ for the British royal family. The failure of the ‘Addled Parliament’ in 1614, gets discussed. Against good advice, King James summoned the parliament and spoke to it on three occasions, all to no avail. Infighting and intransigence doomed the legislative attempts. The narrative arc of 1613 plausibly ends with the Accession Day Tilt on 24 March 1614, a spectacular display in the Whitehall Tiltyard, led by the Duke of Lennox, a fitting end to the exploration of cultural life.Less

The Choice of Title and Registration Systems

Benito Arruñada

in Institutional Foundations of Impersonal Exchange: Theory and Policy of Contractual Registries

This chapter considers the main design choices for registries. It examines the decision whether to create a public titling system or to rely exclusively on private titling; the choice between ... More

This chapter considers the main design choices for registries. It examines the decision whether to create a public titling system or to rely exclusively on private titling; the choice between voluntary and universal titling; the theoretical and empirical consideration of recordation of deeds and registration of rights; and the mostly parallel choices for business registration.Less

In the Chiefest of his Royalty

in Monstrous Adversary: The Life of Edward de Vere, 17th Earl of Oxford

This chapter presents the deponents in the lawsuit against Oxford. Oxford participated in Accession Day tilts from 1578 to 1580. Indications of his expenditures on the tilts come from a formal ... More

This chapter presents the deponents in the lawsuit against Oxford. Oxford participated in Accession Day tilts from 1578 to 1580. Indications of his expenditures on the tilts come from a formal complaint made on 21 May 1598 by Judith Ruswell, widow of William Ruswell (or Russell), tailor, seeking to recover monies never repaid by Oxford. Denying the claim, Oxford conceded that about 1580 he provided Ruswell with a stock of cloth worth £700 or £800. The lawsuit reveals the identities of thirteen deponents who confessed to having known Judith and William Ruswell, and Oxford, the defendant.Less

Geometrical Errors Are the Cost of Maintaining the Luminance Contrast Polarity

Sergio Roncato

in The Oxford Compendium of Visual Illusions

The visual completion is the result of the integration of fragmented contours. The contrast polarity (or contrast sign) may affect this interpolation by strengthening the completion in a direction ... More

The visual completion is the result of the integration of fragmented contours. The contrast polarity (or contrast sign) may affect this interpolation by strengthening the completion in a direction where the contrast polarity is preserved. This chapter illustrates some manifestations of these phenomena: the alteration of the alignment of the visual units and the illusory tilt of more complex visual organization. The occurrence of basic distorting effects underlying classic illusions—such as the Frazer illusion—is discussed. It is noted that the role of the contrast polarity rule in representing a “preferential” rule does not preclude other possibilities, such as edges completion, although it renders the contour detectable to a lesser degree.Less

The Rotating Tilted Lines Illusion: Rotation Instead of Expansion—A Peculiar Case of Motion Misperception

Simone Gori

in The Oxford Compendium of Visual Illusions

This chapter describes the Rotating-Tilted-Lines illusion , which is a new motion illusion that arises in a circular pattern composed by black, radial lines tilted to the right and presented on a ... More

This chapter describes the Rotating-Tilted-Lines illusion , which is a new motion illusion that arises in a circular pattern composed by black, radial lines tilted to the right and presented on a white background. When one approaches the stimulus pattern, the radial lines appear to rotate in the counterclockwise direction, whereas when one recedes from it, they appear to rotate clockwise. It is the simplest pattern able to elicit illusory rotatory motion in presence of physical radial expansion. This surprising misperception of motion seems to be a result of the competition between two motion processing units in the primary visual cortex (V1, V5)Less

Boundary Issues: Reconsidering the Artist’s Sanction

K. E. Gover

in Art and Authority: Moral Rights and Meaning in Contemporary Visual Art

This chapter reconsiders Sherri Irvin’s theory of the ‘artist’s sanction,’ which articulates the authority of artists to determine the boundaries of ontologically innovative works of art through ... More

This chapter reconsiders Sherri Irvin’s theory of the ‘artist’s sanction,’ which articulates the authority of artists to determine the boundaries of ontologically innovative works of art through their public declarations. While this theory shares some similarities with the ‘dual-intention theory’ of art authorship, it is importantly different in scope. The chapter argues that this principle effaces the boundary between the artist’s authority to determine, on the one hand, the disposition of the work as an object-to-be-interpreted and, on the other hand, the proper interpretation of the work. It turns to the example of site-specific artworks to illustrate the theoretical and practical difficulties that can arise when artists use their authority to bestow features of an artwork through their declarations.Less

Ocular Motor Disorders Caused by Lesions in the Cerebellum

Agnes M.F. Wong

in Eye Movement Disorders

The vestibulocerebellum consists of the flocculus, ventral paraflocculus, nodulus, and uvula. ■ The flocculus receives inputs from the vestibular nucleus and nerve, nucleus prepositus hypoglossi ... More

The vestibulocerebellum consists of the flocculus, ventral paraflocculus, nodulus, and uvula. ■ The flocculus receives inputs from the vestibular nucleus and nerve, nucleus prepositus hypoglossi (NPH), inferior olivary nucleus, cell groups of the paramedian tracts (PMT), nucleus reticularis tegmenti pontis (NRTP), and mesencephalic reticular formation. ■ The ventral paraflocculus receives inputs from contralateral pontine nuclei. ■ Project to ipsilateral superior and medial vestibular nuclei, and the y-group ■ Receive input from the medial and inferior vestibular nuclei, vestibular nerve, NPH, and inferior olivary nucleus ■ Project to the vestibular nuclei ■ The oculomotor vermis consists of parts of the declive, folium, tuber, and pyramis. ■ Receives inputs from the inferior olivary nucleus, vestibular nuclei, NPH, paramedian pontine reticular formation (PPRF), NRTP, and dorsolateral and dorsomedial pontine nuclei ■ Projects to the caudal fastigial nucleus ■ Stimulation of the Purkinje cells in the dorsal vermis elicits contralaterally directed saccades and smooth pursuit ■ Receives inputs from the dorsal vermis, inferior olivary nucleus, and NRTP ■ Decussates and projects via the uncinate fasciculus of the brachium conjunctivum to the contralateral PPRF, rostral interstitial nucleus of the medial longitudinal fasciculus, nucleus of the posterior commissure, omnipause neurons in nucleus raphe interpositus, the mesencephalic reticular formation, and superior colliculus ■ Neurons in the fastigial oculomotor region (FOR) fire during both ipsilateral and contralateral saccades. 1. The contralateral FOR neurons burst before the onset of saccade, and the onset of firing is not correlated with any property of the saccade. 2. Conversely, the time of onset for neurons in the ipsilateral FOR varies, with bursts occurring later for larger saccades. 3. Thus, the difference in time of onset between contralateral and ipsilateral FOR activity encodes the amplitude of saccades (i.e., the larger the difference in time of onset, the larger the saccade amplitude). Eye movement abnormalities in uncinate fasciculus lesion include hypometric ipsilesional saccades and hypermetric contralesional saccades (“contrapulsion”). Arnold-Chiari malformation is a malformation of the medullary–spinal junction with herniation of intracranial contents through the foramen magnum. The three types are illustrated in the figure below. Less